Post Formats UI Update, 2/4

Not a whole lot to discuss today – working away at patches on #19570 (edit form UI) and #23347 (theme compat). Could use a patch on #15490 (retrieval of oEmbed data and previewing, which I suspect will become relevant to the edit form UI) and testing of #23282 (audio/video shortcode and player) and #16047 (list table column).